Vehicles entering the Western Harbour Tunnel. The tunnel is the most expensive of the three cross-harbour tunnels and the government is trying to cut tolls on it and raises those on the other two to alleviate congestion. Photo: Edward Wong

Vehicles entering the Western Harbour Tunnel. The tunnel is the most expensive of the three cross-harbour tunnels and the government is trying to cut tolls on it and raises those on the other two to alleviate congestion. Photo: Edward Wong